A good product development process should ensure a good understanding of what is to be developed, how it is to be developed and that it was developed correctly. IEC 61508 and IEC 62443‑4‑1 both have development process requirements. These requirements overlap and separate efforts when assessing compliance to both standards would mean duplicating efforts to assess the common requirements. By identifying what process requirements are in common between IEC 61508 and IEC 62443‑4‑1 and showing that the IEC 61508 process requirements meet the IEC 62443‑4‑1 process requirements, the cost of developing procedures, and assessing procedures for compliance, can be reduced.